Worcester 24-28 Si II (01.10.2005-21.07.2016) Operating instructions

Brand: Worcester

Model: 24-28 Si II (01.10.2005-21.07.2016)

Category: Water heaters & boilers

Type: Operating instructions

Worcester, Bosch Group, Cotswold Way, Warndon, Worcester WR4 9SW.

Telephone: 01905 754624 Fax: 01905 753130.

Technical Helpline 08705 266241.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Limited

6 720 610 414b 10/05

134

Hot Water Mode:

The appliance operates to supply only domestic hot water when

the heating temperature mode is fully anti-clockwise, at the – position

or the timer is programmed to OFF mode.

The flow is limited within the appliance to give a hot water

delivery rate to a maximum of 9.0 (±15%) litres/minute-25Si or 10.0

(±15%) litres/minute-28Si.

Hot Water and

Central Heating

mode:

When a demand is made for

heating by the system controls

(i.e. a programmer or room

thermostat).

The pump will energise

circulating primary water

around the heating system

and the burner will light. The

heat output from the

appliance in this mode has

been factory set to maximum.

The appliance will operate as

necessary to maintain the

temperature of the radiators at

the level set by the adjustment

of the Heating Temperature

Control Knob. (See Fig. 2.)

If the system no longer

requires heat to maintain the

desired room temperature, the

burner will extinguish. The

pump will continue to run for

a short period to dissipate the

residual heat from the

appliance and then switch off.

The appliance will supply

heat to the central heating

system as required. A demand

for hot water at a tap or

shower will override the

central heating function for

the period of the domestic hot

water demand.

GUARANTEE

REGISTRATION

You should complete and return the postpaid Guarantee

Registration Card within 30 days of purchase.

The card will register you as the owner of your new

Worcester Si II appliance and, while this will not affect your

statutory rights in any way, it will assist us to maintain an

effective and efficient customer service by establishing a

reference and permanent record for your boiler.

IMPORTANT: SERIAL NUMBER. Copy the number off the

Guarantee Card.

FOR YOUR OWN RECORD

MODEL

SERIAL NUMBER

TYPE/SIZE DATE OF INSTALLATION

MAINTAINING YOUR

APPLIANCE

Your new Worcester Si gas-fired appliance represents a long-

term investment in a reliable, high quality product.

In order to realise its maximum working life, and to ensure

it continues to operate at peak efficiency and performance, it is

essential that your boiler receives regular, competent servicing

and annual maintenance checks beyond the initial 24 month

guarantee period*.

Regular service contracts can be arranged with your installer

– however if you have difficulty making a satisfactory

arrangement simply contact Worcester on

08457 256206 for help.

If you would like to know more about Worcester’s extended

warranty options please tick the appropriate box on your

warranty registration card.

*subject to terms and conditions on page 15.

Fig. 1. System Diagram.

Automatic air

vent

Primary heat

exchanger

Circulating

pump

Fixed

by-pass

Relief valve

flow

Domestic

hot water

flow

Domestic

cold

supply

return

Relief valve

discharge

Domestic

water flow

turbine

Expansion

vessel

24-28Si

SERIES

USER INSTRUCTIONS &

CUSTOMER CARE GUIDE

G.C. NUMBERS

APPLIANCE NATURAL GAS L.P.G.

24Si II 47 311 65 47 311 66

28Si II 47 311 67 47 311 68

www.worcester-bosch.co.uk

Worcester supports the

Benchmark code of practice

CORGI CONTACT

All CORGI Registered installers carry a CORGI ID card and

have a registration number. Both should be recorded in your

central heating log book

. You can check your installer is

CORGI Registered by calling CORGI on 01256 372300

Vote for your

‘Installer of the year’ at

www.worcester-bosch.co.uk

CONTACT NUMBERS:

UK Contact Centre Tel. 08457 256 206

UK Contact Centre Fax. 01905 757536

Scotland only Fax. 01506 441 687

Eire Tel: 01 494 0099

OPERATING HOURS:

Mon - Fri 7.00am to 8.00pm

Sat 8.00am to 5.00pm

Sun 9.00am to 12.00pm

Please contact our UK Contact Centre number where our friendly

operators will book your call with one of our team of nationwide

engineers.

NOTE:

Please refer to our website for our bank holiday opening hours.

www.worcester-bosch.co.uk

EXCELLENCE COMES

AS STANDARD

Thank you for purchasing a Worcester SiII Series gas-fired

combination appliance.

The SiII Series appliances are made by Worcester and the

strictest quality control standards are demanded throughout

every stage of production.

Indeed, Worcester, part of the Bosch Group have led the

field in innovative

appliance design and

performance for more

than 40 years.

The result is that your

new Worcester SiII

appliance offers you the

very best of everything -

quality, efficiency,

economical running costs,

proven reliability and

value for money.

What’s more, you also have the assurance of our no-

nonsense 1 year parts and labour guarantee.

Page No.

Operating Instructions

.................................... 3-11

Fault and Breakdowns 12

Maintenance and

Extended Warranty

Information ............ 13-14

Guarantee Details ... 15-16

CONTENTS

YOUR WORCESTER

Si II SERIES

GUARANTEE

This appliance is guaranteed from the date of installation

subject to the following conditions & exceptions.

1. The appliance is guaranteed for a

period of 24 calendar months

subject to the return of the

guarantee card within 30 days of

installation and the first 12 months

service and inspection having been

carried out to the satisfaction of BBT

Thermotechnology UK Ltd. Please

note that this service is not covered

under the terms & conditions of the

warranty and would therefore incur

a charge.

2. That during the period of this

guarantee any components of the

unit which are Proved to be faulty

or defective in manufacture will be

exchanged or repaired Free of

material charges and free of labour

charges if repaired directly by BBT

Thermotechnology UK Ltd. Invoices

for attendance and repair of this

appliance by third parties will not

be accepted for payment by BBT.

3. That the householder may be asked

to prove the date of installation and

that the appliance was correctly

commissioned. This information

must then be documented in the

Benchmark Gas Boiler

Commissioning Checklist.

4. That any product or part thereof

returned for servicing under the

guarantee must be accompanied by

a claim stating the model, serial

number and date of installation.

5. That BBT Thermotechnology UK Ltd

will not accept responsibility for

damage caused by faulty

installation, neglect, misuse,

accidental damage or the non-

observance of the instructions

contained in the Installation and

Users instructions leaflets.

6. That the appliance has been used

only for normal domestic purposes,

for which it was designed.

7. That this guarantee applies only to

equipment purchased and used in

mainland Great Britain.

This guarantee is given in addition to all your normal statutory rights.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Ltd.

GENERAL

INFORMATION

GAS SAFETY (INSTALLATION AND USE)

REGULATIONS

It is the law, in GB, that all gas appliances must be installed by a

competent person in accordance with the above regulations. Failure to

install appliances correctly could lead to prosecution. It is in your

interest and that of safety to ensure compliance with the law. The

manufacturer’s notes must not be taken, in any way, as over-riding

statutory obligations.

In GB, a competent person is someone registered with CORGI. All

CORGI registered installers carry a CORGI ID card and have a

registration number. Both should be recorded in the BENCHMARK

checklist. You can check that your installer is CORGI registered by

calling CORGI on 01256 372300.

WARNING: This appliance must be earthed and protected by a 3

amp fuse to BS 1362.

ELECTRICITY SUPPLY: 230V ~ 50Hz

IMPORTANT: To get the best from your Worcester Si II appliance

please read these instructions carefully.

NOTE: In the event of a fault the appliance should not be used

until the fault has been corrected by a competent person.

BENCHMARK

The Benchmark initiative is a code of practice to encourage the

correct installation, commissioning and servicing of domestic central

heating boilers and system equipment.

A checklist can be found in the back of every installation

manual. This is a vital document that needs to be completed by the

installer at the time of installation. It confirms that the boiler has

been installed and commissioned according to the manufacturers

instructions.

In Eire the declaration found in IS 813 must be completed.

Without completion of the checklist and/or declaration,

manufacturers may refuse to respond to a call-out request. It is

important that the checklist and/or declaration are fully completed by

your installer.

GENERAL DESCRIPTION

(See Fig.1.)

The WORCESTER Si II MODELS are combined domestic hot

water and central heating appliances. They consist of a gas fired boiler

having a varying output of between 6.9kW and 24kW (24Si II) or 8.1

and 28kW (28Si II), and all the necessary controls to provide mains fed

domestic hot water and central heating.

The appliances are fitted with a manual ON/OFF Switch.

The appliances can operate in one of two modes. Hot water only

or hot water and central heating.

CONTACT CENTRES

CONTACT NUMBERS:

UK Contact Centre Tel. 08457 256 206

UK Contact Centre Fax. 01905 757536

Scotland only Fax. 01506 441 687

Eire Tel: 01 494 0099

OPERATING HOURS:

Mon - Fri 7.00am to 8.00pm

Sat 8.00am to 5.00pm

Sun 9.00am to 12.00pm

Please contact our UK Contact Centre number where our friendly

operators will book your call with one of our team of nationwide

engineers.

NOTE:

Please refer to our website for our bank holiday opening hours.

www.worcester-bosch.co.uk

EXCELLENCE COMES

AS STANDARD

Thank you for purchasing a Worcester SiII Series gas-fired

combination appliance.

The SiII Series appliances are made by Worcester and the

strictest quality control standards are demanded throughout

every stage of production.

Indeed, Worcester, part of the Bosch Group have led the

field in innovative

appliance design and

performance for more

than 40 years.

The result is that your

new Worcester SiII

appliance offers you the

very best of everything -

quality, efficiency,

economical running costs,

proven reliability and

value for money.

What’s more, you also have the assurance of our no-

nonsense 1 year parts and labour guarantee.

Page No.

Operating Instructions

.................................... 3-11

Fault and Breakdowns 12

Maintenance and

Extended Warranty

Information ............ 13-14

Guarantee Details ... 15-16

CONTENTS

YOUR WORCESTER

Si II SERIES

GUARANTEE

This appliance is guaranteed from the date of installation

subject to the following conditions & exceptions.

1. The appliance is guaranteed for a

period of 24 calendar months

subject to the return of the

guarantee card within 30 days of

installation and the first 12 months

service and inspection having been

carried out to the satisfaction of BBT

Thermotechnology UK Ltd. Please

note that this service is not covered

under the terms & conditions of the

warranty and would therefore incur

a charge.

2. That during the period of this

guarantee any components of the

unit which are Proved to be faulty

or defective in manufacture will be

exchanged or repaired Free of

material charges and free of labour

charges if repaired directly by BBT

Thermotechnology UK Ltd. Invoices

for attendance and repair of this

appliance by third parties will not

be accepted for payment by BBT.

3. That the householder may be asked

to prove the date of installation and

that the appliance was correctly

commissioned. This information

must then be documented in the

Benchmark Gas Boiler

Commissioning Checklist.

4. That any product or part thereof

returned for servicing under the

guarantee must be accompanied by

a claim stating the model, serial

number and date of installation.

5. That BBT Thermotechnology UK Ltd

will not accept responsibility for

damage caused by faulty

installation, neglect, misuse,

accidental damage or the non-

observance of the instructions

contained in the Installation and

Users instructions leaflets.

6. That the appliance has been used

only for normal domestic purposes,

for which it was designed.

7. That this guarantee applies only to

equipment purchased and used in

mainland Great Britain.

This guarantee is given in addition to all your normal statutory rights.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Ltd.

GENERAL

INFORMATION

GAS SAFETY (INSTALLATION AND USE)

REGULATIONS

It is the law, in GB, that all gas appliances must be installed by a

competent person in accordance with the above regulations. Failure to

install appliances correctly could lead to prosecution. It is in your

interest and that of safety to ensure compliance with the law. The

manufacturer’s notes must not be taken, in any way, as over-riding

statutory obligations.

In GB, a competent person is someone registered with CORGI. All

CORGI registered installers carry a CORGI ID card and have a

registration number. Both should be recorded in the BENCHMARK

checklist. You can check that your installer is CORGI registered by

calling CORGI on 01256 372300.

WARNING: This appliance must be earthed and protected by a 3

amp fuse to BS 1362.

ELECTRICITY SUPPLY: 230V ~ 50Hz

IMPORTANT: To get the best from your Worcester Si II appliance

please read these instructions carefully.

NOTE: In the event of a fault the appliance should not be used

until the fault has been corrected by a competent person.

BENCHMARK

The Benchmark initiative is a code of practice to encourage the

correct installation, commissioning and servicing of domestic central

heating boilers and system equipment.

A checklist can be found in the back of every installation

manual. This is a vital document that needs to be completed by the

installer at the time of installation. It confirms that the boiler has

been installed and commissioned according to the manufacturers

instructions.

In Eire the declaration found in IS 813 must be completed.

Without completion of the checklist and/or declaration,

manufacturers may refuse to respond to a call-out request. It is

important that the checklist and/or declaration are fully completed by

your installer.

GENERAL DESCRIPTION

(See Fig.1.)

The WORCESTER Si II MODELS are combined domestic hot

water and central heating appliances. They consist of a gas fired boiler

having a varying output of between 6.9kW and 24kW (24Si II) or 8.1

and 28kW (28Si II), and all the necessary controls to provide mains fed

domestic hot water and central heating.

The appliances are fitted with a manual ON/OFF Switch.

The appliances can operate in one of two modes. Hot water only

or hot water and central heating.

CONTACT CENTRES

Worcester, Bosch Group, Cotswold Way, Warndon, Worcester WR4 9SW.

Telephone: 01905 754624 Fax: 01905 753130.

Technical Helpline 08705 266241.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Limited

6 720 610 414b 10/05

134

Hot Water Mode:

The appliance operates to supply only domestic hot water when

the heating temperature mode is fully anti-clockwise, at the – position

or the timer is programmed to OFF mode.

The flow is limited within the appliance to give a hot water

delivery rate to a maximum of 9.0 (±15%) litres/minute-25Si or 10.0

(±15%) litres/minute-28Si.

Hot Water and

Central Heating

mode:

When a demand is made for

heating by the system controls

(i.e. a programmer or room

thermostat).

The pump will energise

circulating primary water

around the heating system

and the burner will light. The

heat output from the

appliance in this mode has

been factory set to maximum.

The appliance will operate as

necessary to maintain the

temperature of the radiators at

the level set by the adjustment

of the Heating Temperature

Control Knob. (See Fig. 2.)

If the system no longer

requires heat to maintain the

desired room temperature, the

burner will extinguish. The

pump will continue to run for

a short period to dissipate the

residual heat from the

appliance and then switch off.

The appliance will supply

heat to the central heating

system as required. A demand

for hot water at a tap or

shower will override the

central heating function for

the period of the domestic hot

water demand.

GUARANTEE

REGISTRATION

You should complete and return the postpaid Guarantee

Registration Card within 30 days of purchase.

The card will register you as the owner of your new

Worcester Si II appliance and, while this will not affect your

statutory rights in any way, it will assist us to maintain an

effective and efficient customer service by establishing a

reference and permanent record for your boiler.

IMPORTANT: SERIAL NUMBER. Copy the number off the

Guarantee Card.

FOR YOUR OWN RECORD

MODEL

SERIAL NUMBER

TYPE/SIZE DATE OF INSTALLATION

MAINTAINING YOUR

APPLIANCE

Your new Worcester Si gas-fired appliance represents a long-

term investment in a reliable, high quality product.

In order to realise its maximum working life, and to ensure

it continues to operate at peak efficiency and performance, it is

essential that your boiler receives regular, competent servicing

and annual maintenance checks beyond the initial 24 month

guarantee period*.

Regular service contracts can be arranged with your installer

– however if you have difficulty making a satisfactory

arrangement simply contact Worcester on

08457 256206 for help.

If you would like to know more about Worcester’s extended

warranty options please tick the appropriate box on your

warranty registration card.

*subject to terms and conditions on page 15.

Fig. 1. System Diagram.

Automatic air

vent

Primary heat

exchanger

Circulating

pump

Fixed

by-pass

Relief valve

flow

Domestic

hot water

flow

Domestic

cold

supply

return

Relief valve

discharge

Domestic

water flow

turbine

Expansion

vessel

24-28Si

SERIES

USER INSTRUCTIONS &

CUSTOMER CARE GUIDE

G.C. NUMBERS

APPLIANCE NATURAL GAS L.P.G.

24Si II 47 311 65 47 311 66

28Si II 47 311 67 47 311 68

www.worcester-bosch.co.uk

Worcester supports the

Benchmark code of practice

CORGI CONTACT

All CORGI Registered installers carry a CORGI ID card and

have a registration number. Both should be recorded in your

central heating log book

. You can check your installer is

CORGI Registered by calling CORGI on 01256 372300

Vote for your

‘Installer of the year’ at

www.worcester-bosch.co.uk

12 5

CENTRAL HEATING SYSTEM

During the first few hours of operation of the central heating

system, check that all radiators are being heated at an even rate.

Should the upper area of a radiator be at a lower temperature than the

base of the radiator, it should be vented by releasing air through the

venting screw at the top of each radiator. Make sure your installer

shows you how to carry out the operation. Repeated venting will

reduce the quantity of water in the system and this must be

replenished for safe and satisfactory operation of the appliance.

Should water leaks be found in the system or excessive venting be

required from any radiator, a service engineer should be contacted and

the system corrected.

GENERAL NOTES

INDICATOR LIGHTS

Flame detection indicator:

OFF: Burner off

ON: Burner on

OPERATION OF

CONTROLS

More than 30% of all calls made to our contact centre reporting

appliance faults or breakdowns prove to be false alarms, as there is often

a simple explanation for the apparent malfunction.

So, to help you save time and money – not to mention frustration

and inconvenience – please refer to the General Information, Notes and

Lighting Instructions ensuring all controls are set correctly.

If, after following the instructions the appliance still fails to operate

correctly call the Worcester Contact Centre. Arrangements will be made

for an engineer to call as soon as possible.

CALL-OUT CHARGES

All of our field service engineers are factory trained.

If you request a visit from an engineer and your appliance has been

installed within the last 12 months, no charge will be made for parts

and/or labour, providing:

•

The appliance was commissioned correctly on installation.

•

An appliance fault is found and the appliance has been installed

within the past 12 months.

A call-out charge will be made where:

•

The appliance has been installed for over 12 months, or

•

Our Field Service Engineer finds no fault with the appliance (see

note), or

•

The cause of breakdown is with other parts of your

plumbing/heating system, or with equipment not supplied by Worcester.

NOTE: Invoices for attendance and/or repair work carried out on

your appliance by any third party will not be accepted.

APPLIANCE FAILS TO

OPERATE

Fig. 2. Controls.

The appliance is fitted with the following controls:

OPERATING SWITCH

In the ‘0’ position there is no mains electricity to the control

board.

In the ‘I’ position mains electricity is connected to the control

board.

CENTRAL HEATING TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered to the radiators between fully clockwise and anti-

clockwise to the mark. When the knob is turned anti-clockwise

past the position towards the ‘’(Summer Position), then the

appliance will operate in the HOT WATER mode only and no heat will

be delivered to the radiators.

DOMESTIC HOT WATER TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered at the domestic hot water taps between fully

clockwise and anti- clockwise positions.

By slightly reducing the flow of domestic water from the tap, the

delivery temperature of the water will be further increased. This is of

particular advantage in the winter, for example to increase bath water

temperature and to remove heavy grease deposits on plates, etc. Also

this will provide an added advantage of reducing the delay before hot

water is obtained.

FACIA MOUNTED PROGRAMMER (if fitted)

Your installer may have mounted either a mechanical or an

electronic programmer into the facia of your appliance. Operating

instructions are supplied with the programmer.

RESET BUTTON

Press this button in for five seconds if the indicator light is

flashing slowly.

If indicator lamp is flashing fast turn power OFF and ON at the

boiler to reset.

SYSTEM PRESSURE GAUGE

The black needle will show the actual pressure in the system.

When operating the pressure indicated must not be greater than

2.5bar. If it is then contact your installer.

Mains electricity

On/Off

Fault indicator and

reset button

Flame detection

indicator

CH temp

control knob

DHW temp

control knob

System pressure

gauge

▲

The appliance must be fitted to a sealed heating system which is

pre-pressurised. Your installer will advise you on the minimum and

maximum pressure that should be indicated on the pressure gauge.

See Fig. 2. Check regularly that this pressure is maintained and

contact your installer or maintenance engineer if there is a permanent

significant drop in pressure indicated on the gauge. If the system loses

pressure it should be re-pressurised as instructed by the installer (N.B.

Maximum operating pressure 2.5 bar).

SEALED HEATING SYSTEM

▲

Fault indicator:

FLASHING SLOW: Ignition lockout or

(once per second) boiler overheat

FLASHING FAST: Appliance fault

(five times a second)

Your installer will

have provided adequate

space around the

appliance for safety and

servicing. Do not restrict

this space by the

addition of cupboards,

shelves etc. close to the

appliance.

NOTE: If the appliance is to be enclosed after the

installation then the instructions given in Section 6, Air

Supply, of the Installation Book MUST be followed.

ROOM THERMOSTAT

A room thermostat must be fitted for control of the central

heating temperature. It will be located in one room of the home. The

method of setting a room thermostat varies with the type and

manufacture. Refer to the instructions supplied with the room

thermostat.

THERMOSTATIC RADIATOR VALVES

If thermostatic radiator valves are fitted to the system then they

must conform to the requirements of BS2767. The radiator located in

the room where the room thermostat is sited must be controlled by a

thermostatic radiator valve.

SHOWERS, BIDETS, TAPS AND MIXING

VALVES

Standard hot and cold taps and mixing valves used with the

appliance must be suitable for operating at mains pressure.

Thermostatically controlled shower valves will guard against the flow

of water at too high a temperature.

If using a pressure equalising valve, set the Domestic Hot Water

temperature control knob to the ‘MAX’ position.

Hot and cold mains fed water can be supplied direct to an

overrim flushing bidet subject to local water company requirements.

With all mains fed systems the flow of water from the individual

taps will vary with the number of outlets operated simultaneously

and the cold water mains supply pressure to the property. Flow

balancing using ‘Ball-o-Fix’ type valves is recommended to avoid an

excessive reduction in flow to individual outlets.

For further information contact The Worcester Technical

Helpline.

HOT AND COLD FLOW

If the flow of water demanded from both hot and cold service

outlets is dependent upon mains supply, it may not be possible in

some installations to operate all outlets simultaneously.

WATER MAINS FAILURE

It is important to note that in the event of a mains water supply

failure, no tap water will be available until the mains supply is

restored. The appliance can still be used for heating provided that the

system is of the sealed system type.

TO LIGHT THE APPLIANCE

Check that the water valves to the central heating circuit are open.

Check that the black needle on the pressure gauge is not below

the required pressure.

Switch on the mains electricity. Set the room thermostat to

maximum. Turn the central heating temperature control knob fully

clockwise.

The burner will light and the red flame detection indicator will light.

Set the central heating and hot water temperature control knobs

and the room thermostat, if fitted, to the desired temperature.

TO STOP THE APPLIANCE

For Short Periods

Turn the central heating temperature control knob fully anti-

clockwise to the ‘O’ position.

For Long Periods

Turn the operating switch to the ‘O’ position. Switch off the

mains electricity.

A facia mounted electronic programmer will retain its settings for

about two weeks, after which it will return to the factory set

programme. The time will be saved for approximately 7 hours. The

display will disappear after approximately 1 hour.

A facia mounted mechanical programmer will require resetting

once the operating switch has been set to ‘O’, or the mains supply has

been disconnected.

ELECTRICITY SUPPLY

FAILURE

If the electricity supply fails the appliance will not operate. Once

the supply is restored the appliance will return to normal operation. If

a programmer is fitted, check that the settings have been maintained.

OVERHEAT CUT-OFF

THERMOSTAT

The appliance will enter a lockout condition in the event of

overheating.

An overheat cut-off thermostat is fitted to the appliance which

will interrupt the electricity supply to the gas valve.

If the overheat cut-off has operated, the fault indicator will flash

once a second. If this condition continues to occur, then call a service

engineer.

The appliance can be reset by pressing the fault indicator button

and holding in for 5 seconds when the appliance has cooled.

USE IN HARD WATER AREAS

Normally there is no need for scale protection. However, in areas

of exceptionally hard water supply it is recommended that an In-Line

scale inhibitor be fitted.

Installation should be strictly in accordance with the

requirements of the local Water Company. An isolating valve to

facilitate servicing should be incorporated.

The water hardness may be determined using the standard test

paper or by reference to the local Water Company.

Further information may be obtained from The Worcester

Technical Helpline.

VENTILATION OF ROOM SEALED FANNED

FLUE (RSF) APPLIANCES

These are room sealed appliances and any ventilation openings

in a wall or door must not be obstructed. Do not allow the flue

terminal fitted on the outside wall to become obstructed or damaged.

NOTE: Do not place anything on top of the appliance.

If the appliance is fitted in a compartment do not use the

compartment for storage purposes unless it conforms to the

requirements of BS 6798:1987: Section 6. It is essential that the airing

space is separated from the boiler space by a perforated non-

combustible partition as described in BS 6798:1987.

CIRCULATING PUMP

This may be fitted with a speed adjuster. If so it will be factory

set at maximum and should not be changed.

FROST PRECAUTIONS

If the appliance is not to be used for a long period of time and

there is a likelihood of freezing, then the appliance should be drained.

The Worcester Technical Helpline will advise you on suitable frost

precautions. For short periods the built-in frost protection of the

appliance will be adequate.

SERVICE

Annual servicing is important in order to ensure continuing high

efficiency and long life for your appliance. In the event of any

difficulty in making suitable servicing arrangements, Worcester

personnel or other competent persons will discuss regular servicing

arrangements and offer a comprehensive maintenance contract.

WARNING

If a gas leak exists, or is suspected, turn off the gas supply to the

appliance at the service cock and consult your local service engineer.

Do not touch any electrical switches to turn them either on or off.

Open all windows and doors. Do not smoke. Extinguish all naked lights.

CLEANING

Do not use abrasive cleaners on the outer casing. Use a damp

cloth and a little detergent.

Under no circumstances should any seal on the boiler be broken.

IGNITION LOCKOUT

The appliance will enter a lockout condition in the event of the

burner failing to ignite.

If the burner fails to light after 5 attempts the electricity supply

to the gas valve will be interrupted.

If ignition lockout has occurred, the fault indicator will flash

slowly (approximately once per second).

The appliance can be reset by pressing the reset button and

holding in for 5 seconds. Check that the gas supply has not been

interrupted.

If this condition continues to occur, then call a service engineer.

AIR FLOW DEVICE

The appliance will enter a lockout condition in the event of an

air flow fault.

If the controls fail to detect the correct air flow through the

appliance the electricity supply to the gas valve will be interrupted.

If an air flow fault has occurred, the fault indicator will flash

(approximately five times per second).

The appliance will try to re-light after a waiting period of

approximately 5 minutes Check that the flue terminal has not been

obstructed or damaged.

If this condition continues to occur, then call a service engineer.

TO LIGHT AND STOP THE

APPLIANCE

RSF

Left-hand side 10 80

Right-hand side 10 80

In Front 600 240

Above the casing 180 30

Below 200 200

CLEARANCES

Unventilated

compartment

above flue elbow

or turret

Minimum clearances in millimetres.

Your installer will

have provided adequate

space around the

appliance for safety and

servicing. Do not restrict

this space by the

addition of cupboards,

shelves etc. close to the

appliance.

NOTE: If the appliance is to be enclosed after the

installation then the instructions given in Section 6, Air

Supply, of the Installation Book MUST be followed.

ROOM THERMOSTAT

A room thermostat must be fitted for control of the central

heating temperature. It will be located in one room of the home. The

method of setting a room thermostat varies with the type and

manufacture. Refer to the instructions supplied with the room

thermostat.

THERMOSTATIC RADIATOR VALVES

If thermostatic radiator valves are fitted to the system then they

must conform to the requirements of BS2767. The radiator located in

the room where the room thermostat is sited must be controlled by a

thermostatic radiator valve.

SHOWERS, BIDETS, TAPS AND MIXING

VALVES

Standard hot and cold taps and mixing valves used with the

appliance must be suitable for operating at mains pressure.

Thermostatically controlled shower valves will guard against the flow

of water at too high a temperature.

If using a pressure equalising valve, set the Domestic Hot Water

temperature control knob to the ‘MAX’ position.

Hot and cold mains fed water can be supplied direct to an

overrim flushing bidet subject to local water company requirements.

With all mains fed systems the flow of water from the individual

taps will vary with the number of outlets operated simultaneously

and the cold water mains supply pressure to the property. Flow

balancing using ‘Ball-o-Fix’ type valves is recommended to avoid an

excessive reduction in flow to individual outlets.

For further information contact The Worcester Technical

Helpline.

HOT AND COLD FLOW

If the flow of water demanded from both hot and cold service

outlets is dependent upon mains supply, it may not be possible in

some installations to operate all outlets simultaneously.

WATER MAINS FAILURE

It is important to note that in the event of a mains water supply

failure, no tap water will be available until the mains supply is

restored. The appliance can still be used for heating provided that the

system is of the sealed system type.

TO LIGHT THE APPLIANCE

Check that the water valves to the central heating circuit are open.

Check that the black needle on the pressure gauge is not below

the required pressure.

Switch on the mains electricity. Set the room thermostat to

maximum. Turn the central heating temperature control knob fully

clockwise.

The burner will light and the red flame detection indicator will light.

Set the central heating and hot water temperature control knobs

and the room thermostat, if fitted, to the desired temperature.

TO STOP THE APPLIANCE

For Short Periods

Turn the central heating temperature control knob fully anti-

clockwise to the ‘O’ position.

For Long Periods

Turn the operating switch to the ‘O’ position. Switch off the

mains electricity.

A facia mounted electronic programmer will retain its settings for

about two weeks, after which it will return to the factory set

programme. The time will be saved for approximately 7 hours. The

display will disappear after approximately 1 hour.

A facia mounted mechanical programmer will require resetting

once the operating switch has been set to ‘O’, or the mains supply has

been disconnected.

ELECTRICITY SUPPLY

FAILURE

If the electricity supply fails the appliance will not operate. Once

the supply is restored the appliance will return to normal operation. If

a programmer is fitted, check that the settings have been maintained.

OVERHEAT CUT-OFF

THERMOSTAT

The appliance will enter a lockout condition in the event of

overheating.

An overheat cut-off thermostat is fitted to the appliance which

will interrupt the electricity supply to the gas valve.

If the overheat cut-off has operated, the fault indicator will flash

once a second. If this condition continues to occur, then call a service

engineer.

The appliance can be reset by pressing the fault indicator button

and holding in for 5 seconds when the appliance has cooled.

USE IN HARD WATER AREAS

Normally there is no need for scale protection. However, in areas

of exceptionally hard water supply it is recommended that an In-Line

scale inhibitor be fitted.

Installation should be strictly in accordance with the

requirements of the local Water Company. An isolating valve to

facilitate servicing should be incorporated.

The water hardness may be determined using the standard test

paper or by reference to the local Water Company.

Further information may be obtained from The Worcester

Technical Helpline.

VENTILATION OF ROOM SEALED FANNED

FLUE (RSF) APPLIANCES

These are room sealed appliances and any ventilation openings

in a wall or door must not be obstructed. Do not allow the flue

terminal fitted on the outside wall to become obstructed or damaged.

NOTE: Do not place anything on top of the appliance.

If the appliance is fitted in a compartment do not use the

compartment for storage purposes unless it conforms to the

requirements of BS 6798:1987: Section 6. It is essential that the airing

space is separated from the boiler space by a perforated non-

combustible partition as described in BS 6798:1987.

CIRCULATING PUMP

This may be fitted with a speed adjuster. If so it will be factory

set at maximum and should not be changed.

FROST PRECAUTIONS

If the appliance is not to be used for a long period of time and

there is a likelihood of freezing, then the appliance should be drained.

The Worcester Technical Helpline will advise you on suitable frost

precautions. For short periods the built-in frost protection of the

appliance will be adequate.

SERVICE

Annual servicing is important in order to ensure continuing high

efficiency and long life for your appliance. In the event of any

difficulty in making suitable servicing arrangements, Worcester

personnel or other competent persons will discuss regular servicing

arrangements and offer a comprehensive maintenance contract.

WARNING

If a gas leak exists, or is suspected, turn off the gas supply to the

appliance at the service cock and consult your local service engineer.

Do not touch any electrical switches to turn them either on or off.

Open all windows and doors. Do not smoke. Extinguish all naked lights.

CLEANING

Do not use abrasive cleaners on the outer casing. Use a damp

cloth and a little detergent.

Under no circumstances should any seal on the boiler be broken.

IGNITION LOCKOUT

The appliance will enter a lockout condition in the event of the

burner failing to ignite.

If the burner fails to light after 5 attempts the electricity supply

to the gas valve will be interrupted.

If ignition lockout has occurred, the fault indicator will flash

slowly (approximately once per second).

The appliance can be reset by pressing the reset button and

holding in for 5 seconds. Check that the gas supply has not been

interrupted.

If this condition continues to occur, then call a service engineer.

AIR FLOW DEVICE

The appliance will enter a lockout condition in the event of an

air flow fault.

If the controls fail to detect the correct air flow through the

appliance the electricity supply to the gas valve will be interrupted.

If an air flow fault has occurred, the fault indicator will flash

(approximately five times per second).

The appliance will try to re-light after a waiting period of

approximately 5 minutes Check that the flue terminal has not been

obstructed or damaged.

If this condition continues to occur, then call a service engineer.

TO LIGHT AND STOP THE

APPLIANCE

RSF

Left-hand side 10 80

Right-hand side 10 80

In Front 600 240

Above the casing 180 30

Below 200 200

CLEARANCES

Unventilated

compartment

above flue elbow

or turret

Minimum clearances in millimetres.

12 5

CENTRAL HEATING SYSTEM

During the first few hours of operation of the central heating

system, check that all radiators are being heated at an even rate.

Should the upper area of a radiator be at a lower temperature than the

base of the radiator, it should be vented by releasing air through the

venting screw at the top of each radiator. Make sure your installer

shows you how to carry out the operation. Repeated venting will

reduce the quantity of water in the system and this must be

replenished for safe and satisfactory operation of the appliance.

Should water leaks be found in the system or excessive venting be

required from any radiator, a service engineer should be contacted and

the system corrected.

GENERAL NOTES

INDICATOR LIGHTS

Flame detection indicator:

OFF: Burner off

ON: Burner on

OPERATION OF

CONTROLS

More than 30% of all calls made to our contact centre reporting

appliance faults or breakdowns prove to be false alarms, as there is often

a simple explanation for the apparent malfunction.

So, to help you save time and money – not to mention frustration

and inconvenience – please refer to the General Information, Notes and

Lighting Instructions ensuring all controls are set correctly.

If, after following the instructions the appliance still fails to operate

correctly call the Worcester Contact Centre. Arrangements will be made

for an engineer to call as soon as possible.

CALL-OUT CHARGES

All of our field service engineers are factory trained.

If you request a visit from an engineer and your appliance has been

installed within the last 12 months, no charge will be made for parts

and/or labour, providing:

•

The appliance was commissioned correctly on installation.

•

An appliance fault is found and the appliance has been installed

within the past 12 months.

A call-out charge will be made where:

•

The appliance has been installed for over 12 months, or

•

Our Field Service Engineer finds no fault with the appliance (see

note), or

•

The cause of breakdown is with other parts of your

plumbing/heating system, or with equipment not supplied by Worcester.

NOTE: Invoices for attendance and/or repair work carried out on

your appliance by any third party will not be accepted.

APPLIANCE FAILS TO

OPERATE

Fig. 2. Controls.

The appliance is fitted with the following controls:

OPERATING SWITCH

In the ‘0’ position there is no mains electricity to the control

board.

In the ‘I’ position mains electricity is connected to the control

board.

CENTRAL HEATING TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered to the radiators between fully clockwise and anti-

clockwise to the mark. When the knob is turned anti-clockwise

past the position towards the ‘’(Summer Position), then the

appliance will operate in the HOT WATER mode only and no heat will

be delivered to the radiators.

DOMESTIC HOT WATER TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered at the domestic hot water taps between fully

clockwise and anti- clockwise positions.

By slightly reducing the flow of domestic water from the tap, the

delivery temperature of the water will be further increased. This is of

particular advantage in the winter, for example to increase bath water

temperature and to remove heavy grease deposits on plates, etc. Also

this will provide an added advantage of reducing the delay before hot

water is obtained.

FACIA MOUNTED PROGRAMMER (if fitted)

Your installer may have mounted either a mechanical or an

electronic programmer into the facia of your appliance. Operating

instructions are supplied with the programmer.

RESET BUTTON

Press this button in for five seconds if the indicator light is

flashing slowly.

If indicator lamp is flashing fast turn power OFF and ON at the

boiler to reset.

SYSTEM PRESSURE GAUGE

The black needle will show the actual pressure in the system.

When operating the pressure indicated must not be greater than

2.5bar. If it is then contact your installer.

Mains electricity

On/Off

Fault indicator and

reset button

Flame detection

indicator

CH temp

control knob

DHW temp

control knob

System pressure

gauge

▲

The appliance must be fitted to a sealed heating system which is

pre-pressurised. Your installer will advise you on the minimum and

maximum pressure that should be indicated on the pressure gauge.

See Fig. 2. Check regularly that this pressure is maintained and

contact your installer or maintenance engineer if there is a permanent

significant drop in pressure indicated on the gauge. If the system loses

pressure it should be re-pressurised as instructed by the installer (N.B.

Maximum operating pressure 2.5 bar).

SEALED HEATING SYSTEM

▲

Fault indicator:

FLASHING SLOW: Ignition lockout or

(once per second) boiler overheat

FLASHING FAST: Appliance fault

(five times a second)

12 5

CENTRAL HEATING SYSTEM

During the first few hours of operation of the central heating

system, check that all radiators are being heated at an even rate.

Should the upper area of a radiator be at a lower temperature than the

base of the radiator, it should be vented by releasing air through the

venting screw at the top of each radiator. Make sure your installer

shows you how to carry out the operation. Repeated venting will

reduce the quantity of water in the system and this must be

replenished for safe and satisfactory operation of the appliance.

Should water leaks be found in the system or excessive venting be

required from any radiator, a service engineer should be contacted and

the system corrected.

GENERAL NOTES

INDICATOR LIGHTS

Flame detection indicator:

OFF: Burner off

ON: Burner on

OPERATION OF

CONTROLS

More than 30% of all calls made to our contact centre reporting

appliance faults or breakdowns prove to be false alarms, as there is often

a simple explanation for the apparent malfunction.

So, to help you save time and money – not to mention frustration

and inconvenience – please refer to the General Information, Notes and

Lighting Instructions ensuring all controls are set correctly.

If, after following the instructions the appliance still fails to operate

correctly call the Worcester Contact Centre. Arrangements will be made

for an engineer to call as soon as possible.

CALL-OUT CHARGES

All of our field service engineers are factory trained.

If you request a visit from an engineer and your appliance has been

installed within the last 12 months, no charge will be made for parts

and/or labour, providing:

•

The appliance was commissioned correctly on installation.

•

An appliance fault is found and the appliance has been installed

within the past 12 months.

A call-out charge will be made where:

•

The appliance has been installed for over 12 months, or

•

Our Field Service Engineer finds no fault with the appliance (see

note), or

•

The cause of breakdown is with other parts of your

plumbing/heating system, or with equipment not supplied by Worcester.

NOTE: Invoices for attendance and/or repair work carried out on

your appliance by any third party will not be accepted.

APPLIANCE FAILS TO

OPERATE

Fig. 2. Controls.

The appliance is fitted with the following controls:

OPERATING SWITCH

In the ‘0’ position there is no mains electricity to the control

board.

In the ‘I’ position mains electricity is connected to the control

board.

CENTRAL HEATING TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered to the radiators between fully clockwise and anti-

clockwise to the mark. When the knob is turned anti-clockwise

past the position towards the ‘’(Summer Position), then the

appliance will operate in the HOT WATER mode only and no heat will

be delivered to the radiators.

DOMESTIC HOT WATER TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered at the domestic hot water taps between fully

clockwise and anti- clockwise positions.

By slightly reducing the flow of domestic water from the tap, the

delivery temperature of the water will be further increased. This is of

particular advantage in the winter, for example to increase bath water

temperature and to remove heavy grease deposits on plates, etc. Also

this will provide an added advantage of reducing the delay before hot

water is obtained.

FACIA MOUNTED PROGRAMMER (if fitted)

Your installer may have mounted either a mechanical or an

electronic programmer into the facia of your appliance. Operating

instructions are supplied with the programmer.

RESET BUTTON

Press this button in for five seconds if the indicator light is

flashing slowly.

If indicator lamp is flashing fast turn power OFF and ON at the

boiler to reset.

SYSTEM PRESSURE GAUGE

The black needle will show the actual pressure in the system.

When operating the pressure indicated must not be greater than

2.5bar. If it is then contact your installer.

Mains electricity

On/Off

Fault indicator and

reset button

Flame detection

indicator

CH temp

control knob

DHW temp

control knob

System pressure

gauge

▲

The appliance must be fitted to a sealed heating system which is

pre-pressurised. Your installer will advise you on the minimum and

maximum pressure that should be indicated on the pressure gauge.

See Fig. 2. Check regularly that this pressure is maintained and

contact your installer or maintenance engineer if there is a permanent

significant drop in pressure indicated on the gauge. If the system loses

pressure it should be re-pressurised as instructed by the installer (N.B.

Maximum operating pressure 2.5 bar).

SEALED HEATING SYSTEM

▲

Fault indicator:

FLASHING SLOW: Ignition lockout or

(once per second) boiler overheat

FLASHING FAST: Appliance fault

(five times a second)

Your installer will

have provided adequate

space around the

appliance for safety and

servicing. Do not restrict

this space by the

addition of cupboards,

shelves etc. close to the

appliance.

NOTE: If the appliance is to be enclosed after the

installation then the instructions given in Section 6, Air

Supply, of the Installation Book MUST be followed.

ROOM THERMOSTAT

A room thermostat must be fitted for control of the central

heating temperature. It will be located in one room of the home. The

method of setting a room thermostat varies with the type and

manufacture. Refer to the instructions supplied with the room

thermostat.

THERMOSTATIC RADIATOR VALVES

If thermostatic radiator valves are fitted to the system then they

must conform to the requirements of BS2767. The radiator located in

the room where the room thermostat is sited must be controlled by a

thermostatic radiator valve.

SHOWERS, BIDETS, TAPS AND MIXING

VALVES

Standard hot and cold taps and mixing valves used with the

appliance must be suitable for operating at mains pressure.

Thermostatically controlled shower valves will guard against the flow

of water at too high a temperature.

If using a pressure equalising valve, set the Domestic Hot Water

temperature control knob to the ‘MAX’ position.

Hot and cold mains fed water can be supplied direct to an

overrim flushing bidet subject to local water company requirements.

With all mains fed systems the flow of water from the individual

taps will vary with the number of outlets operated simultaneously

and the cold water mains supply pressure to the property. Flow

balancing using ‘Ball-o-Fix’ type valves is recommended to avoid an

excessive reduction in flow to individual outlets.

For further information contact The Worcester Technical

Helpline.

HOT AND COLD FLOW

If the flow of water demanded from both hot and cold service

outlets is dependent upon mains supply, it may not be possible in

some installations to operate all outlets simultaneously.

WATER MAINS FAILURE

It is important to note that in the event of a mains water supply

failure, no tap water will be available until the mains supply is

restored. The appliance can still be used for heating provided that the

system is of the sealed system type.

TO LIGHT THE APPLIANCE

Check that the water valves to the central heating circuit are open.

Check that the black needle on the pressure gauge is not below

the required pressure.

Switch on the mains electricity. Set the room thermostat to

maximum. Turn the central heating temperature control knob fully

clockwise.

The burner will light and the red flame detection indicator will light.

Set the central heating and hot water temperature control knobs

and the room thermostat, if fitted, to the desired temperature.

TO STOP THE APPLIANCE

For Short Periods

Turn the central heating temperature control knob fully anti-

clockwise to the ‘O’ position.

For Long Periods

Turn the operating switch to the ‘O’ position. Switch off the

mains electricity.

A facia mounted electronic programmer will retain its settings for

about two weeks, after which it will return to the factory set

programme. The time will be saved for approximately 7 hours. The

display will disappear after approximately 1 hour.

A facia mounted mechanical programmer will require resetting

once the operating switch has been set to ‘O’, or the mains supply has

been disconnected.

ELECTRICITY SUPPLY

FAILURE

If the electricity supply fails the appliance will not operate. Once

the supply is restored the appliance will return to normal operation. If

a programmer is fitted, check that the settings have been maintained.

OVERHEAT CUT-OFF

THERMOSTAT

The appliance will enter a lockout condition in the event of

overheating.

An overheat cut-off thermostat is fitted to the appliance which

will interrupt the electricity supply to the gas valve.

If the overheat cut-off has operated, the fault indicator will flash

once a second. If this condition continues to occur, then call a service

engineer.

The appliance can be reset by pressing the fault indicator button

and holding in for 5 seconds when the appliance has cooled.

USE IN HARD WATER AREAS

Normally there is no need for scale protection. However, in areas

of exceptionally hard water supply it is recommended that an In-Line

scale inhibitor be fitted.

Installation should be strictly in accordance with the

requirements of the local Water Company. An isolating valve to

facilitate servicing should be incorporated.

The water hardness may be determined using the standard test

paper or by reference to the local Water Company.

Further information may be obtained from The Worcester

Technical Helpline.

VENTILATION OF ROOM SEALED FANNED

FLUE (RSF) APPLIANCES

These are room sealed appliances and any ventilation openings

in a wall or door must not be obstructed. Do not allow the flue

terminal fitted on the outside wall to become obstructed or damaged.

NOTE: Do not place anything on top of the appliance.

If the appliance is fitted in a compartment do not use the

compartment for storage purposes unless it conforms to the

requirements of BS 6798:1987: Section 6. It is essential that the airing

space is separated from the boiler space by a perforated non-

combustible partition as described in BS 6798:1987.

CIRCULATING PUMP

This may be fitted with a speed adjuster. If so it will be factory

set at maximum and should not be changed.

FROST PRECAUTIONS

If the appliance is not to be used for a long period of time and

there is a likelihood of freezing, then the appliance should be drained.

The Worcester Technical Helpline will advise you on suitable frost

precautions. For short periods the built-in frost protection of the

appliance will be adequate.

SERVICE

Annual servicing is important in order to ensure continuing high

efficiency and long life for your appliance. In the event of any

difficulty in making suitable servicing arrangements, Worcester

personnel or other competent persons will discuss regular servicing

arrangements and offer a comprehensive maintenance contract.

WARNING

If a gas leak exists, or is suspected, turn off the gas supply to the

appliance at the service cock and consult your local service engineer.

Do not touch any electrical switches to turn them either on or off.

Open all windows and doors. Do not smoke. Extinguish all naked lights.

CLEANING

Do not use abrasive cleaners on the outer casing. Use a damp

cloth and a little detergent.

Under no circumstances should any seal on the boiler be broken.

IGNITION LOCKOUT

The appliance will enter a lockout condition in the event of the

burner failing to ignite.

If the burner fails to light after 5 attempts the electricity supply

to the gas valve will be interrupted.

If ignition lockout has occurred, the fault indicator will flash

slowly (approximately once per second).

The appliance can be reset by pressing the reset button and

holding in for 5 seconds. Check that the gas supply has not been

interrupted.

If this condition continues to occur, then call a service engineer.

AIR FLOW DEVICE

The appliance will enter a lockout condition in the event of an

air flow fault.

If the controls fail to detect the correct air flow through the

appliance the electricity supply to the gas valve will be interrupted.

If an air flow fault has occurred, the fault indicator will flash

(approximately five times per second).

The appliance will try to re-light after a waiting period of

approximately 5 minutes Check that the flue terminal has not been

obstructed or damaged.

If this condition continues to occur, then call a service engineer.

TO LIGHT AND STOP THE

APPLIANCE

RSF

Left-hand side 10 80

Right-hand side 10 80

In Front 600 240

Above the casing 180 30

Below 200 200

CLEARANCES

Unventilated

compartment

above flue elbow

or turret

Minimum clearances in millimetres.

Your installer will

have provided adequate

space around the

appliance for safety and

servicing. Do not restrict

this space by the

addition of cupboards,

shelves etc. close to the

appliance.

NOTE: If the appliance is to be enclosed after the

installation then the instructions given in Section 6, Air

Supply, of the Installation Book MUST be followed.

ROOM THERMOSTAT

A room thermostat must be fitted for control of the central

heating temperature. It will be located in one room of the home. The

method of setting a room thermostat varies with the type and

manufacture. Refer to the instructions supplied with the room

thermostat.

THERMOSTATIC RADIATOR VALVES

If thermostatic radiator valves are fitted to the system then they

must conform to the requirements of BS2767. The radiator located in

the room where the room thermostat is sited must be controlled by a

thermostatic radiator valve.

SHOWERS, BIDETS, TAPS AND MIXING

VALVES

Standard hot and cold taps and mixing valves used with the

appliance must be suitable for operating at mains pressure.

Thermostatically controlled shower valves will guard against the flow

of water at too high a temperature.

If using a pressure equalising valve, set the Domestic Hot Water

temperature control knob to the ‘MAX’ position.

Hot and cold mains fed water can be supplied direct to an

overrim flushing bidet subject to local water company requirements.

With all mains fed systems the flow of water from the individual

taps will vary with the number of outlets operated simultaneously

and the cold water mains supply pressure to the property. Flow

balancing using ‘Ball-o-Fix’ type valves is recommended to avoid an

excessive reduction in flow to individual outlets.

For further information contact The Worcester Technical

Helpline.

HOT AND COLD FLOW

If the flow of water demanded from both hot and cold service

outlets is dependent upon mains supply, it may not be possible in

some installations to operate all outlets simultaneously.

WATER MAINS FAILURE

It is important to note that in the event of a mains water supply

failure, no tap water will be available until the mains supply is

restored. The appliance can still be used for heating provided that the

system is of the sealed system type.

TO LIGHT THE APPLIANCE

Check that the water valves to the central heating circuit are open.

Check that the black needle on the pressure gauge is not below

the required pressure.

Switch on the mains electricity. Set the room thermostat to

maximum. Turn the central heating temperature control knob fully

clockwise.

The burner will light and the red flame detection indicator will light.

Set the central heating and hot water temperature control knobs

and the room thermostat, if fitted, to the desired temperature.

TO STOP THE APPLIANCE

For Short Periods

Turn the central heating temperature control knob fully anti-

clockwise to the ‘O’ position.

For Long Periods

Turn the operating switch to the ‘O’ position. Switch off the

mains electricity.

A facia mounted electronic programmer will retain its settings for

about two weeks, after which it will return to the factory set

programme. The time will be saved for approximately 7 hours. The

display will disappear after approximately 1 hour.

A facia mounted mechanical programmer will require resetting

once the operating switch has been set to ‘O’, or the mains supply has

been disconnected.

ELECTRICITY SUPPLY

FAILURE

If the electricity supply fails the appliance will not operate. Once

the supply is restored the appliance will return to normal operation. If

a programmer is fitted, check that the settings have been maintained.

OVERHEAT CUT-OFF

THERMOSTAT

The appliance will enter a lockout condition in the event of

overheating.

An overheat cut-off thermostat is fitted to the appliance which

will interrupt the electricity supply to the gas valve.

If the overheat cut-off has operated, the fault indicator will flash

once a second. If this condition continues to occur, then call a service

engineer.

The appliance can be reset by pressing the fault indicator button

and holding in for 5 seconds when the appliance has cooled.

USE IN HARD WATER AREAS

Normally there is no need for scale protection. However, in areas

of exceptionally hard water supply it is recommended that an In-Line

scale inhibitor be fitted.

Installation should be strictly in accordance with the

requirements of the local Water Company. An isolating valve to

facilitate servicing should be incorporated.

The water hardness may be determined using the standard test

paper or by reference to the local Water Company.

Further information may be obtained from The Worcester

Technical Helpline.

VENTILATION OF ROOM SEALED FANNED

FLUE (RSF) APPLIANCES

These are room sealed appliances and any ventilation openings

in a wall or door must not be obstructed. Do not allow the flue

terminal fitted on the outside wall to become obstructed or damaged.

NOTE: Do not place anything on top of the appliance.

If the appliance is fitted in a compartment do not use the

compartment for storage purposes unless it conforms to the

requirements of BS 6798:1987: Section 6. It is essential that the airing

space is separated from the boiler space by a perforated non-

combustible partition as described in BS 6798:1987.

CIRCULATING PUMP

This may be fitted with a speed adjuster. If so it will be factory

set at maximum and should not be changed.

FROST PRECAUTIONS

If the appliance is not to be used for a long period of time and

there is a likelihood of freezing, then the appliance should be drained.

The Worcester Technical Helpline will advise you on suitable frost

precautions. For short periods the built-in frost protection of the

appliance will be adequate.

SERVICE

Annual servicing is important in order to ensure continuing high

efficiency and long life for your appliance. In the event of any

difficulty in making suitable servicing arrangements, Worcester

personnel or other competent persons will discuss regular servicing

arrangements and offer a comprehensive maintenance contract.

WARNING

If a gas leak exists, or is suspected, turn off the gas supply to the

appliance at the service cock and consult your local service engineer.

Do not touch any electrical switches to turn them either on or off.

Open all windows and doors. Do not smoke. Extinguish all naked lights.

CLEANING

Do not use abrasive cleaners on the outer casing. Use a damp

cloth and a little detergent.

Under no circumstances should any seal on the boiler be broken.

IGNITION LOCKOUT

The appliance will enter a lockout condition in the event of the

burner failing to ignite.

If the burner fails to light after 5 attempts the electricity supply

to the gas valve will be interrupted.

If ignition lockout has occurred, the fault indicator will flash

slowly (approximately once per second).

The appliance can be reset by pressing the reset button and

holding in for 5 seconds. Check that the gas supply has not been

interrupted.

If this condition continues to occur, then call a service engineer.

AIR FLOW DEVICE

The appliance will enter a lockout condition in the event of an

air flow fault.

If the controls fail to detect the correct air flow through the

appliance the electricity supply to the gas valve will be interrupted.

If an air flow fault has occurred, the fault indicator will flash

(approximately five times per second).

The appliance will try to re-light after a waiting period of

approximately 5 minutes Check that the flue terminal has not been

obstructed or damaged.

If this condition continues to occur, then call a service engineer.

TO LIGHT AND STOP THE

APPLIANCE

RSF

Left-hand side 10 80

Right-hand side 10 80

In Front 600 240

Above the casing 180 30

Below 200 200

CLEARANCES

Unventilated

compartment

above flue elbow

or turret

Minimum clearances in millimetres.

12 5

CENTRAL HEATING SYSTEM

During the first few hours of operation of the central heating

system, check that all radiators are being heated at an even rate.

Should the upper area of a radiator be at a lower temperature than the

base of the radiator, it should be vented by releasing air through the

venting screw at the top of each radiator. Make sure your installer

shows you how to carry out the operation. Repeated venting will

reduce the quantity of water in the system and this must be

replenished for safe and satisfactory operation of the appliance.

Should water leaks be found in the system or excessive venting be

required from any radiator, a service engineer should be contacted and

the system corrected.

GENERAL NOTES

INDICATOR LIGHTS

Flame detection indicator:

OFF: Burner off

ON: Burner on

OPERATION OF

CONTROLS

More than 30% of all calls made to our contact centre reporting

appliance faults or breakdowns prove to be false alarms, as there is often

a simple explanation for the apparent malfunction.

So, to help you save time and money – not to mention frustration

and inconvenience – please refer to the General Information, Notes and

Lighting Instructions ensuring all controls are set correctly.

If, after following the instructions the appliance still fails to operate

correctly call the Worcester Contact Centre. Arrangements will be made

for an engineer to call as soon as possible.

CALL-OUT CHARGES

All of our field service engineers are factory trained.

If you request a visit from an engineer and your appliance has been

installed within the last 12 months, no charge will be made for parts

and/or labour, providing:

•

The appliance was commissioned correctly on installation.

•

An appliance fault is found and the appliance has been installed

within the past 12 months.

A call-out charge will be made where:

•

The appliance has been installed for over 12 months, or

•

Our Field Service Engineer finds no fault with the appliance (see

note), or

•

The cause of breakdown is with other parts of your

plumbing/heating system, or with equipment not supplied by Worcester.

NOTE: Invoices for attendance and/or repair work carried out on

your appliance by any third party will not be accepted.

APPLIANCE FAILS TO

OPERATE

Fig. 2. Controls.

The appliance is fitted with the following controls:

OPERATING SWITCH

In the ‘0’ position there is no mains electricity to the control

board.

In the ‘I’ position mains electricity is connected to the control

board.

CENTRAL HEATING TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered to the radiators between fully clockwise and anti-

clockwise to the mark. When the knob is turned anti-clockwise

past the position towards the ‘’(Summer Position), then the

appliance will operate in the HOT WATER mode only and no heat will

be delivered to the radiators.

DOMESTIC HOT WATER TEMPERATURE

CONTROL

The position of this knob will determine the temperature of the

water delivered at the domestic hot water taps between fully

clockwise and anti- clockwise positions.

By slightly reducing the flow of domestic water from the tap, the

delivery temperature of the water will be further increased. This is of

particular advantage in the winter, for example to increase bath water

temperature and to remove heavy grease deposits on plates, etc. Also

this will provide an added advantage of reducing the delay before hot

water is obtained.

FACIA MOUNTED PROGRAMMER (if fitted)

Your installer may have mounted either a mechanical or an

electronic programmer into the facia of your appliance. Operating

instructions are supplied with the programmer.

RESET BUTTON

Press this button in for five seconds if the indicator light is

flashing slowly.

If indicator lamp is flashing fast turn power OFF and ON at the

boiler to reset.

SYSTEM PRESSURE GAUGE

The black needle will show the actual pressure in the system.

When operating the pressure indicated must not be greater than

2.5bar. If it is then contact your installer.

Mains electricity

On/Off

Fault indicator and

reset button

Flame detection

indicator

CH temp

control knob

DHW temp

control knob

System pressure

gauge

▲

The appliance must be fitted to a sealed heating system which is

pre-pressurised. Your installer will advise you on the minimum and

maximum pressure that should be indicated on the pressure gauge.

See Fig. 2. Check regularly that this pressure is maintained and

contact your installer or maintenance engineer if there is a permanent

significant drop in pressure indicated on the gauge. If the system loses

pressure it should be re-pressurised as instructed by the installer (N.B.

Maximum operating pressure 2.5 bar).

SEALED HEATING SYSTEM

▲

Fault indicator:

FLASHING SLOW: Ignition lockout or

(once per second) boiler overheat

FLASHING FAST: Appliance fault

(five times a second)

Worcester, Bosch Group, Cotswold Way, Warndon, Worcester WR4 9SW.

Telephone: 01905 754624 Fax: 01905 753130.

Technical Helpline 08705 266241.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Limited

6 720 610 414b 10/05

134

Hot Water Mode:

The appliance operates to supply only domestic hot water when

the heating temperature mode is fully anti-clockwise, at the – position

or the timer is programmed to OFF mode.

The flow is limited within the appliance to give a hot water

delivery rate to a maximum of 9.0 (±15%) litres/minute-25Si or 10.0

(±15%) litres/minute-28Si.

Hot Water and

Central Heating

mode:

When a demand is made for

heating by the system controls

(i.e. a programmer or room

thermostat).

The pump will energise

circulating primary water

around the heating system

and the burner will light. The

heat output from the

appliance in this mode has

been factory set to maximum.

The appliance will operate as

necessary to maintain the

temperature of the radiators at

the level set by the adjustment

of the Heating Temperature

Control Knob. (See Fig. 2.)

If the system no longer

requires heat to maintain the

desired room temperature, the

burner will extinguish. The

pump will continue to run for

a short period to dissipate the

residual heat from the

appliance and then switch off.

The appliance will supply

heat to the central heating

system as required. A demand

for hot water at a tap or

shower will override the

central heating function for

the period of the domestic hot

water demand.

GUARANTEE

REGISTRATION

You should complete and return the postpaid Guarantee

Registration Card within 30 days of purchase.

The card will register you as the owner of your new

Worcester Si II appliance and, while this will not affect your

statutory rights in any way, it will assist us to maintain an

effective and efficient customer service by establishing a

reference and permanent record for your boiler.

IMPORTANT: SERIAL NUMBER. Copy the number off the

Guarantee Card.

FOR YOUR OWN RECORD

MODEL

SERIAL NUMBER

TYPE/SIZE DATE OF INSTALLATION

MAINTAINING YOUR

APPLIANCE

Your new Worcester Si gas-fired appliance represents a long-

term investment in a reliable, high quality product.

In order to realise its maximum working life, and to ensure

it continues to operate at peak efficiency and performance, it is

essential that your boiler receives regular, competent servicing

and annual maintenance checks beyond the initial 24 month

guarantee period*.

Regular service contracts can be arranged with your installer

– however if you have difficulty making a satisfactory

arrangement simply contact Worcester on

08457 256206 for help.

If you would like to know more about Worcester’s extended

warranty options please tick the appropriate box on your

warranty registration card.

*subject to terms and conditions on page 15.

Fig. 1. System Diagram.

Automatic air

vent

Primary heat

exchanger

Circulating

pump

Fixed

by-pass

Relief valve

flow

Domestic

hot water

flow

Domestic

cold

supply

return

Relief valve

discharge

Domestic

water flow

turbine

Expansion

vessel

24-28Si

SERIES

USER INSTRUCTIONS &

CUSTOMER CARE GUIDE

G.C. NUMBERS

APPLIANCE NATURAL GAS L.P.G.

24Si II 47 311 65 47 311 66

28Si II 47 311 67 47 311 68

www.worcester-bosch.co.uk

Worcester supports the

Benchmark code of practice

CORGI CONTACT

All CORGI Registered installers carry a CORGI ID card and

have a registration number. Both should be recorded in your

central heating log book

. You can check your installer is

CORGI Registered by calling CORGI on 01256 372300

Vote for your

‘Installer of the year’ at

www.worcester-bosch.co.uk

CONTACT NUMBERS:

UK Contact Centre Tel. 08457 256 206

UK Contact Centre Fax. 01905 757536

Scotland only Fax. 01506 441 687

Eire Tel: 01 494 0099

OPERATING HOURS:

Mon - Fri 7.00am to 8.00pm

Sat 8.00am to 5.00pm

Sun 9.00am to 12.00pm

Please contact our UK Contact Centre number where our friendly

operators will book your call with one of our team of nationwide

engineers.

NOTE:

Please refer to our website for our bank holiday opening hours.

www.worcester-bosch.co.uk

EXCELLENCE COMES

AS STANDARD

Thank you for purchasing a Worcester SiII Series gas-fired

combination appliance.

The SiII Series appliances are made by Worcester and the

strictest quality control standards are demanded throughout

every stage of production.

Indeed, Worcester, part of the Bosch Group have led the

field in innovative

appliance design and

performance for more

than 40 years.

The result is that your

new Worcester SiII

appliance offers you the

very best of everything -

quality, efficiency,

economical running costs,

proven reliability and

value for money.

What’s more, you also have the assurance of our no-

nonsense 1 year parts and labour guarantee.

Page No.

Operating Instructions

.................................... 3-11

Fault and Breakdowns 12

Maintenance and

Extended Warranty

Information ............ 13-14

Guarantee Details ... 15-16

CONTENTS

YOUR WORCESTER

Si II SERIES

GUARANTEE

This appliance is guaranteed from the date of installation

subject to the following conditions & exceptions.

1. The appliance is guaranteed for a

period of 24 calendar months

subject to the return of the

guarantee card within 30 days of

installation and the first 12 months

service and inspection having been

carried out to the satisfaction of BBT

Thermotechnology UK Ltd. Please

note that this service is not covered

under the terms & conditions of the

warranty and would therefore incur

a charge.

2. That during the period of this

guarantee any components of the

unit which are Proved to be faulty

or defective in manufacture will be

exchanged or repaired Free of

material charges and free of labour

charges if repaired directly by BBT

Thermotechnology UK Ltd. Invoices

for attendance and repair of this

appliance by third parties will not

be accepted for payment by BBT.

3. That the householder may be asked

to prove the date of installation and

that the appliance was correctly

commissioned. This information

must then be documented in the

Benchmark Gas Boiler

Commissioning Checklist.

4. That any product or part thereof

returned for servicing under the

guarantee must be accompanied by

a claim stating the model, serial

number and date of installation.

5. That BBT Thermotechnology UK Ltd

will not accept responsibility for

damage caused by faulty

installation, neglect, misuse,

accidental damage or the non-

observance of the instructions

contained in the Installation and

Users instructions leaflets.

6. That the appliance has been used

only for normal domestic purposes,

for which it was designed.

7. That this guarantee applies only to

equipment purchased and used in

mainland Great Britain.

This guarantee is given in addition to all your normal statutory rights.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Ltd.

GENERAL

INFORMATION

GAS SAFETY (INSTALLATION AND USE)

REGULATIONS

It is the law, in GB, that all gas appliances must be installed by a

competent person in accordance with the above regulations. Failure to

install appliances correctly could lead to prosecution. It is in your

interest and that of safety to ensure compliance with the law. The

manufacturer’s notes must not be taken, in any way, as over-riding

statutory obligations.

In GB, a competent person is someone registered with CORGI. All

CORGI registered installers carry a CORGI ID card and have a

registration number. Both should be recorded in the BENCHMARK

checklist. You can check that your installer is CORGI registered by

calling CORGI on 01256 372300.

WARNING: This appliance must be earthed and protected by a 3

amp fuse to BS 1362.

ELECTRICITY SUPPLY: 230V ~ 50Hz

IMPORTANT: To get the best from your Worcester Si II appliance

please read these instructions carefully.

NOTE: In the event of a fault the appliance should not be used

until the fault has been corrected by a competent person.

BENCHMARK

The Benchmark initiative is a code of practice to encourage the

correct installation, commissioning and servicing of domestic central

heating boilers and system equipment.

A checklist can be found in the back of every installation

manual. This is a vital document that needs to be completed by the

installer at the time of installation. It confirms that the boiler has

been installed and commissioned according to the manufacturers

instructions.

In Eire the declaration found in IS 813 must be completed.

Without completion of the checklist and/or declaration,

manufacturers may refuse to respond to a call-out request. It is

important that the checklist and/or declaration are fully completed by

your installer.

GENERAL DESCRIPTION

(See Fig.1.)

The WORCESTER Si II MODELS are combined domestic hot

water and central heating appliances. They consist of a gas fired boiler

having a varying output of between 6.9kW and 24kW (24Si II) or 8.1

and 28kW (28Si II), and all the necessary controls to provide mains fed

domestic hot water and central heating.

The appliances are fitted with a manual ON/OFF Switch.

The appliances can operate in one of two modes. Hot water only

or hot water and central heating.

CONTACT CENTRES

CONTACT NUMBERS:

UK Contact Centre Tel. 08457 256 206

UK Contact Centre Fax. 01905 757536

Scotland only Fax. 01506 441 687

Eire Tel: 01 494 0099

OPERATING HOURS:

Mon - Fri 7.00am to 8.00pm

Sat 8.00am to 5.00pm

Sun 9.00am to 12.00pm

Please contact our UK Contact Centre number where our friendly

operators will book your call with one of our team of nationwide

engineers.

NOTE:

Please refer to our website for our bank holiday opening hours.

www.worcester-bosch.co.uk

EXCELLENCE COMES

AS STANDARD

Thank you for purchasing a Worcester SiII Series gas-fired

combination appliance.

The SiII Series appliances are made by Worcester and the

strictest quality control standards are demanded throughout

every stage of production.

Indeed, Worcester, part of the Bosch Group have led the

field in innovative

appliance design and

performance for more

than 40 years.

The result is that your

new Worcester SiII

appliance offers you the

very best of everything -

quality, efficiency,

economical running costs,

proven reliability and

value for money.

What’s more, you also have the assurance of our no-

nonsense 1 year parts and labour guarantee.

Page No.

Operating Instructions

.................................... 3-11

Fault and Breakdowns 12

Maintenance and

Extended Warranty

Information ............ 13-14

Guarantee Details ... 15-16

CONTENTS

YOUR WORCESTER

Si II SERIES

GUARANTEE

This appliance is guaranteed from the date of installation

subject to the following conditions & exceptions.

1. The appliance is guaranteed for a

period of 24 calendar months

subject to the return of the

guarantee card within 30 days of

installation and the first 12 months

service and inspection having been

carried out to the satisfaction of BBT

Thermotechnology UK Ltd. Please

note that this service is not covered

under the terms & conditions of the

warranty and would therefore incur

a charge.

2. That during the period of this

guarantee any components of the

unit which are Proved to be faulty

or defective in manufacture will be

exchanged or repaired Free of

material charges and free of labour

charges if repaired directly by BBT

Thermotechnology UK Ltd. Invoices

for attendance and repair of this

appliance by third parties will not

be accepted for payment by BBT.

3. That the householder may be asked

to prove the date of installation and

that the appliance was correctly

commissioned. This information

must then be documented in the

Benchmark Gas Boiler

Commissioning Checklist.

4. That any product or part thereof

returned for servicing under the

guarantee must be accompanied by

a claim stating the model, serial

number and date of installation.

5. That BBT Thermotechnology UK Ltd

will not accept responsibility for

damage caused by faulty

installation, neglect, misuse,

accidental damage or the non-

observance of the instructions

contained in the Installation and

Users instructions leaflets.

6. That the appliance has been used

only for normal domestic purposes,

for which it was designed.

7. That this guarantee applies only to

equipment purchased and used in

mainland Great Britain.

This guarantee is given in addition to all your normal statutory rights.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Ltd.

GENERAL

INFORMATION

GAS SAFETY (INSTALLATION AND USE)

REGULATIONS

It is the law, in GB, that all gas appliances must be installed by a

competent person in accordance with the above regulations. Failure to

install appliances correctly could lead to prosecution. It is in your

interest and that of safety to ensure compliance with the law. The

manufacturer’s notes must not be taken, in any way, as over-riding

statutory obligations.

In GB, a competent person is someone registered with CORGI. All

CORGI registered installers carry a CORGI ID card and have a

registration number. Both should be recorded in the BENCHMARK

checklist. You can check that your installer is CORGI registered by

calling CORGI on 01256 372300.

WARNING: This appliance must be earthed and protected by a 3

amp fuse to BS 1362.

ELECTRICITY SUPPLY: 230V ~ 50Hz

IMPORTANT: To get the best from your Worcester Si II appliance

please read these instructions carefully.

NOTE: In the event of a fault the appliance should not be used

until the fault has been corrected by a competent person.

BENCHMARK

The Benchmark initiative is a code of practice to encourage the

correct installation, commissioning and servicing of domestic central

heating boilers and system equipment.

A checklist can be found in the back of every installation

manual. This is a vital document that needs to be completed by the

installer at the time of installation. It confirms that the boiler has

been installed and commissioned according to the manufacturers

instructions.

In Eire the declaration found in IS 813 must be completed.

Without completion of the checklist and/or declaration,

manufacturers may refuse to respond to a call-out request. It is

important that the checklist and/or declaration are fully completed by

your installer.

GENERAL DESCRIPTION

(See Fig.1.)

The WORCESTER Si II MODELS are combined domestic hot

water and central heating appliances. They consist of a gas fired boiler

having a varying output of between 6.9kW and 24kW (24Si II) or 8.1

and 28kW (28Si II), and all the necessary controls to provide mains fed

domestic hot water and central heating.

The appliances are fitted with a manual ON/OFF Switch.

The appliances can operate in one of two modes. Hot water only

or hot water and central heating.

CONTACT CENTRES

Worcester, Bosch Group, Cotswold Way, Warndon, Worcester WR4 9SW.

Telephone: 01905 754624 Fax: 01905 753130.

Technical Helpline 08705 266241.

Worcester, Bosch Group is a trading name of BBT Thermotechnology UK Limited

6 720 610 414b 10/05

134

Hot Water Mode:

The appliance operates to supply only domestic hot water when

the heating temperature mode is fully anti-clockwise, at the – position

or the timer is programmed to OFF mode.

The flow is limited within the appliance to give a hot water

delivery rate to a maximum of 9.0 (±15%) litres/minute-25Si or 10.0

(±15%) litres/minute-28Si.

Hot Water and

Central Heating

mode:

When a demand is made for

heating by the system controls

(i.e. a programmer or room

thermostat).

The pump will energise

circulating primary water

around the heating system

and the burner will light. The

heat output from the

appliance in this mode has

been factory set to maximum.

The appliance will operate as

necessary to maintain the

temperature of the radiators at

the level set by the adjustment

of the Heating Temperature

Control Knob. (See Fig. 2.)

If the system no longer

requires heat to maintain the

desired room temperature, the

burner will extinguish. The

pump will continue to run for

a short period to dissipate the

residual heat from the

appliance and then switch off.

The appliance will supply

heat to the central heating

system as required. A demand

for hot water at a tap or

shower will override the

central heating function for

the period of the domestic hot

water demand.

GUARANTEE

REGISTRATION

You should complete and return the postpaid Guarantee

Registration Card within 30 days of purchase.

The card will register you as the owner of your new

Worcester Si II appliance and, while this will not affect your

statutory rights in any way, it will assist us to maintain an

effective and efficient customer service by establishing a

reference and permanent record for your boiler.

IMPORTANT: SERIAL NUMBER. Copy the number off the

Guarantee Card.

FOR YOUR OWN RECORD

MODEL

SERIAL NUMBER

TYPE/SIZE DATE OF INSTALLATION

MAINTAINING YOUR

APPLIANCE

Your new Worcester Si gas-fired appliance represents a long-

term investment in a reliable, high quality product.

In order to realise its maximum working life, and to ensure

it continues to operate at peak efficiency and performance, it is

essential that your boiler receives regular, competent servicing

and annual maintenance checks beyond the initial 24 month

guarantee period*.

Regular service contracts can be arranged with your installer

– however if you have difficulty making a satisfactory

arrangement simply contact Worcester on

08457 256206 for help.

If you would like to know more about Worcester’s extended

warranty options please tick the appropriate box on your

warranty registration card.

*subject to terms and conditions on page 15.

Fig. 1. System Diagram.

Automatic air

vent

Primary heat

exchanger

Circulating

pump

Fixed

by-pass

Relief valve

flow

Domestic

hot water

flow

Domestic

cold

supply

return

Relief valve

discharge

Domestic

water flow

turbine

Expansion

vessel

24-28Si

SERIES

USER INSTRUCTIONS &

CUSTOMER CARE GUIDE

G.C. NUMBERS

APPLIANCE NATURAL GAS L.P.G.

24Si II 47 311 65 47 311 66

28Si II 47 311 67 47 311 68

www.worcester-bosch.co.uk

Worcester supports the

Benchmark code of practice

CORGI CONTACT

All CORGI Registered installers carry a CORGI ID card and

have a registration number. Both should be recorded in your

central heating log book

. You can check your installer is

CORGI Registered by calling CORGI on 01256 372300

Vote for your

‘Installer of the year’ at

www.worcester-bosch.co.uk

Worcester 24-28 Si II (01.10.2005-21.07.2016) Operating instructions

Brand: Worcester

Model: 24-28 Si II (01.10.2005-21.07.2016)

Category: Water heaters & boilers

Type: Operating instructions

Download PDF

report

Worcester 24-28 Si II (01.10.2005-21.07.2016) Operating instructions

Worcester 24-28 Si II (01.10.2005-21.07.2016) Operating instructions

Related papers

Other documents